Method and apparatus for fabricating polymer-based electroluminescent displays

Abstract

A method for fabricating an electroluminescent display and the substrate and apparatus used therein. The display is preferably constructed on a pre-constructed substrate that includes a flexible base layer having a conducting surface on one side thereof. The base layer is impermeable to oxygen and water. The substrate includes a plurality of wells defined by a barrier layer, each well having an electrode layer connected electrically with the conducting surface. A removable protective layer covering the wells protects the electrode layer from attack by oxygen and water prior to being utilized to make the display. In one embodiment, each of the wells also contains an electron transfer layer in contact with the electrode layer.

What is claimed is:  
     
       1. A method for fabricating an electroluminescent display, said method comprising: 
       providing a substrate comprising a flexible base layer having a conducting surface on one side thereof, said base layer being at least 1000 times less permeable to oxygen and water than a PET film of the same thickness as said base layer, said substrate further comprising a plurality of wells defined by a barrier layer, each of said wells having an electrode layer connected electrically with said conducting surface;  
       moving a first dispenser relative to said substrate so as to quantitatively deposit a first electroluminescent material on said substrate, different amounts of said first electroluminescent material being deposited at different locations on said substrate in response to signals defining an illumination pattern to be generated by said display; and  
       depositing a conducting material on said first electroluminescent material.  
     
     
       2. The method of  claim 1 , further comprising the step of quantitatively depositing a second electroluminescent material on said substrate, said second electroluminescent material emitting light at a different wavelength than said first electroluminescent material. 
     
     
       3. The method of  claim 1 , wherein said conducting material comprises a hole transport material that facilitates the injection of holes into said first electroluminescent material. 
     
     
       4. The method of  claim 1 , wherein said conducting material comprises an electron transport material that facilitates the injection of electrons into said first electroluminescent material. 
     
     
       5. The method of  claim 1 , further comprising the step of depositing a non-luminescent material on said substrate at locations on said display that are not to emit light prior to depositing said conductive material. 
     
     
       6. The method of  claim 5 , wherein said non-luminescent material is an electrical insulator.